This Core Facility will serve as a technical and scientific support unit for three projects (#1, #2, #3) in this Program Project. Its major goals involve 1) the production of radiolabeled and nonradiolabeled analogs in suitable quantities to fulfill the needs of the research laboratories; 2) the testing of all new analogs for their affinities for the cannabinoid receptor; 3) the testing of the "successful covalent ligands" for their abilities to irreversibly bind to the cannabinoid receptor; 4) the biochemical and pharmacological characterization of the ligands. The biochemical and pharmacological characterization of all successful ligands will involve the determination of their activities as agonists or antagonists (reversible and irreversible). Biochemically, the analogs will be tested a) for their effects on adenylate cyclase as a functional test; b) for their partitioning properties in the membrane. The pharmacological characterization will include peripheral in vitro tests for the cannabinoid receptor including their effects on the electrically- evoked contractions of the mouse vas deferens and/or guinea pig myenteric plexus preparation; b) in vivo bioassays in mice to measure locomotor activity, hypothermia, antinociception and ring immobility (Pertwee ring test).